How do I know if my airflow sensor is bad?

How do I know if my airflow sensor is bad?

3 Signs of a Bad Mass Air Flow Sensor

  1. Stalling, jerking, or hesitation during acceleration.
  2. air fuel ratio is too rich.
  3. air fuel ratio is too lean.

How do you test an air sensor?

Set your meter at or close to 10 V DC. Start the engine and let it idle. Backprobe the signal and ground wires (red probe to signal and black probe to ground). Depending on your MAF sensor, your voltage reading should be between 0.60 to 0.80 volts at idle.

What is a normal mass air flow sensor reading?

With the engine at idle, the MAF’s PID value should read anywhere from 2 to 7 grams/second (g/s) at idle and rise to between 15 to 25 g/s at 2500 rpm, depending on engine size. Most manufacturers provide specifications for air flow at idle; some will provide specifications at several engine speeds.

How do you change a mass airflow sensor on a BMW?


  1. Open the hood of your BMW.
  2. Locate the mass air flow sensor by the engine air filter housing on the driver’s side.
  3. Unplug the electrical connector from your BMW mass air flow sensor.
  4. Remove the Torx screws that hold the mass air flow sensor in place.
  5. Install the new MAF on your BMW.

How much does it cost to replace MAF sensor?

The average cost to have the mass airflow sensor replaced is between $200 and $350.

What happens if you disconnect mass air flow sensor?

If you unplug the mass air flow sensor the car will start. If you try to plug it in while it’s running the car will die.

What happens if you unplug MAF sensor?

Where is the camshaft position sensor on a BMW 325i?

Connect camshaft position sensor electrical connector, peel back electrical connector sealing boot (green arrow). Insert a backprobe into terminal 2, the middle terminal. Then connect the red lead of your DVOM to backprobe. Hold sensor while moving a wrench across tip.

How to replace mass air flow in BMW 325i?

Loosen the air flow meter clamp (green arrow), then disconnect the duct from the air flow meter and remove the air filter housing from your engine compartment. Place the air filter housing on a workbench and disconnect the mass air flow sensor retaining tabs on both sides of the sensor by pulling them off.

When to check mass air flow on BMW E46?

A mass airflow meter would usually set a fault code when you are driving, or at a higher RPM. You can check your fault code freeze frame data using an OBD II scan tool, similar to how you would check for fault codes. In this tech article I will show you how to replace the mass airflow sensor on the BMW E46.

Where is Terminal 2 on a BMW sensor?

Terminal 2 is sensor reference voltage / signal wire (yellow arrow). Terminal 3 is the ground for the sensor provided by the DME (purple arrow). Wiring color and DME terminal locations may vary. Check your model against a wiring diagram.